Heavy Freezing Spray Warning 78, NWS Anchorage, AK

963 
FZAK52 PAFC 230046
CWFALU

Coastal Waters Forecast
National Weather Service Anchorage Alaska
346 PM AKST Mon Feb 22 2021

Coastal Waters Forecast for Southwest Alaska+Bristol Bay+The
Alaska Peninsula Waters and the Aleutian Islands up to 100 nm out.

Wind forecasts reflect the predominant speed and direction
expected. Sea forecasts represent an average of the highest
one-third of the combined wind wave and swell height.

PKZ199-231330-
346 PM AKST Mon Feb 22 2021
.SYNOPSIS FOR SOUTHWEST ALASKA+BRISTOL BAY+THE ALASKA
PENINSULA WATERS AND THE ALEUTIAN ISLANDS...

A 986 mb low 135 nm southeast of Attu Island moves to 175 nm west
of Saint Paul Island at 991 mb Tue afternoon then to 175 nm west 
of Saint Matthew Island at 994 mb by Wed afternoon. A 992 mb low 
180 nm west of Saint Paul Island moves to 80 nm west of Saint 
Matthew Island by Tue morning at 995 mb then dissipates by Tue 
afternoon. A front enters the Western Bering by Wed morning.

$$

PKZ150-231330-
South of the AK Peninsula Sitkinak to Castle Cape-
346 PM AKST Mon Feb 22 2021

...SMALL CRAFT ADVISORY THROUGH TUESDAY NIGHT...

.TONIGHT...SW wind 20 kt. Seas 11 ft.
.TUE...S wind 20 kt. Seas 9 ft. Freezing spray N of Chirikof Island.
.TUE NIGHT...Variable wind 15 kt. Seas 8 ft. Rain and snow.
.WED...W wind 35 kt. Seas 13 ft.
.WED NIGHT...W wind 30 kt. Seas 13 ft.
.THU...SW wind 30 kt. Seas 13 ft.
.FRI...S wind 25 kt. Seas 14 ft.
.SAT...W wind 30 kt. Seas 15 ft.

$$

PKZ155-231330-
South of the AK Peninsula Castle Cape to Cape Sarichef-
346 PM AKST Mon Feb 22 2021

...SMALL CRAFT ADVISORY THROUGH TUESDAY NIGHT...

.TONIGHT...S wind 30 kt. Seas 13 ft.
.TUE...S wind 25 kt. Seas 12 ft.
.TUE NIGHT...S wind 20 kt becoming SW 30 kt after midnight. Seas
10 ft. Rain.
.WED AND WED NIGHT...SW wind 30 kt. Seas 15 ft.
.THU...SW wind 30 kt. Seas 13 ft.
.FRI...S wind 25 kt. Seas 14 ft.
.SAT...W wind 30 kt. Seas 19 ft.

$$

PKZ160-231330-
Bristol Bay-
346 PM AKST Mon Feb 22 2021

...HEAVY FREEZING SPRAY WARNING THROUGH TUESDAY...
...SMALL CRAFT ADVISORY TONIGHT...

.TONIGHT...E wind increasing to 25 kt. Seas in ice free waters 4 ft.
Heavy freezing spray.
.TUE...S wind 20 kt. Seas in ice free waters 5 ft. Heavy freezing 
spray. Snow.
.TUE NIGHT...SE wind 20 kt. Seas in ice free waters 5 ft. Snow.
.WED...SW wind 25 kt. Seas in ice free waters 5 ft.
.WED NIGHT...SW wind 30 kt. Seas in ice free waters 7 ft.
.THU...SW wind 30 kt. Seas in ice free waters 10 ft.
.FRI...S wind 20 kt. Seas in ice free waters 5 ft.
.SAT...W wind 25 kt. Seas in ice free waters 7 ft.

$$

PKZ165-231330-
Port Heiden to Cape Sarichef-
346 PM AKST Mon Feb 22 2021

...SMALL CRAFT ADVISORY THROUGH TUESDAY NIGHT...

.TONIGHT...S wind 30 kt. Seas 7 ft. Freezing spray.
.TUE...S wind 25 kt. Seas 7 ft.
.TUE NIGHT...SW wind 25 kt. Seas 7 ft.
.WED AND WED NIGHT...SW wind 30 kt. Seas 11 ft.
.THU...S wind 30 kt. Seas 12 ft.
.FRI...S wind 25 kt. Seas 8 ft.
.SAT...W wind 30 kt. Seas 17 ft.

$$

PKZ170-231330-
Cape Sarichef to Nikolski Bering Side-
346 PM AKST Mon Feb 22 2021

...SMALL CRAFT ADVISORY THROUGH TUESDAY NIGHT...

.TONIGHT...S wind 25 kt. Seas 10 ft.
.TUE...S wind 25 kt. Seas 6 ft.
.TUE NIGHT...SW wind 30 kt. Seas 11 ft.
.WED AND WED NIGHT...SW wind 30 kt. Seas 12 ft.
.THU THROUGH FRI...S wind 30 kt. Seas 12 ft.
.SAT...SW wind 30 kt. Seas 24 ft.

$$

PKZ171-231330-
Unalaska Bay-
346 PM AKST Mon Feb 22 2021

...SMALL CRAFT ADVISORY TONIGHT AND TUESDAY NIGHT...

.TONIGHT...S wind 25 kt diminishing to 10 kt after midnight. Seas
3 ft. Rain.
.TUE...S wind 10 kt. Seas 2 ft. Rain.
.TUE NIGHT...SW wind 15 kt increasing to 25 kt after midnight.
Seas 3 ft.
.WED...SW wind 25 kt. Seas 4 ft.
.WED NIGHT...SW wind 20 kt. Seas 3 ft.
.THU THROUGH FRI...S wind 20 kt. Seas 3 ft.
.SAT...SW wind 25 kt. Seas 4 ft.

$$

PKZ172-231330-
Cape Sarichef to Nikolski Pacific Side-
346 PM AKST Mon Feb 22 2021

...SMALL CRAFT ADVISORY THROUGH TUESDAY NIGHT...

.TONIGHT...S wind 30 kt. Seas 15 ft. Rain.
.TUE...S wind 25 kt. Seas 14 ft. Rain.
.TUE NIGHT...SW wind 30 kt. Seas 15 ft.
.WED...SW wind 35 kt. Seas 15 ft.
.WED NIGHT...SW wind 25 kt. Seas 15 ft.
.THU THROUGH FRI...S wind 30 kt. Seas 15 ft.
.SAT...W wind 30 kt. Seas 19 ft.

$$

PKZ173-231330-
Nikolski to Seguam Island Bering Side-
346 PM AKST Mon Feb 22 2021

...SMALL CRAFT ADVISORY THROUGH TUESDAY NIGHT...

.TONIGHT...SW wind 20 kt becoming S 30 kt after midnight. Seas
10 ft.
.TUE...S wind 30 kt. Seas 10 ft.
.TUE NIGHT...SW wind 30 kt. Seas 11 ft.
.WED AND WED NIGHT...SW wind 30 kt. Seas 11 ft.
.THU...S wind 30 kt. Seas 13 ft.
.FRI THROUGH SAT...SW wind 30 kt. Seas 23 ft.

$$

PKZ174-231330-
Nikolski to Seguam Island Pacific Side-
346 PM AKST Mon Feb 22 2021

...SMALL CRAFT ADVISORY THROUGH TUESDAY NIGHT...

.TONIGHT...SW wind 20 kt becoming S 30 kt after midnight. Seas
16 ft.
.TUE...SW wind 25 kt. Seas 16 ft.
.TUE NIGHT...SW wind 30 kt. Seas 17 ft.
.WED...SW wind 35 kt. Seas 16 ft.
.WED NIGHT...SW wind 25 kt. Seas 14 ft.
.THU...S wind 35 kt. Seas 19 ft.
.FRI THROUGH SAT...SW wind 30 kt. Seas 21 ft.

$$

PKZ175-231330-
Seguam Island to Adak Bering Side-
346 PM AKST Mon Feb 22 2021

...SMALL CRAFT ADVISORY THROUGH TUESDAY NIGHT...

.TONIGHT...S wind 30 kt. Seas 9 ft. Rain and snow showers.
.TUE...SW wind 30 kt. Seas 10 ft.
.TUE NIGHT...W wind 30 kt becoming S 25 kt after midnight. Seas 9 
ft. Snow.
.WED AND WED NIGHT...SW wind 30 kt. Seas 13 ft.
.THU...SE wind 30 kt. Seas 11 ft.
.FRI THROUGH SAT...SW wind 30 kt. Seas 21 ft.

$$

PKZ176-231330-
Seguam Island to Adak Pacific Side-
346 PM AKST Mon Feb 22 2021

...SMALL CRAFT ADVISORY THROUGH TUESDAY NIGHT...

.TONIGHT...S wind 30 kt. Seas 17 ft.
.TUE...SW wind 30 kt. Seas 18 ft.
.TUE NIGHT...SW wind 30 kt. Seas 18 ft. Rain and snow.
.WED...SW wind 35 kt. Seas 15 ft.
.WED NIGHT...S wind 25 kt. Seas 14 ft.
.THU...S wind 35 kt. Seas 20 ft.
.FRI THROUGH SAT...SW wind 30 kt. Seas 18 ft.

$$

PKZ177-231330-
Adak to Kiska-
346 PM AKST Mon Feb 22 2021

...GALE WARNING TUESDAY NIGHT...

.TONIGHT...S wind 30 kt. Seas 12 ft Bering side...19 ft Pacific 
side. Rain and snow showers.
.TUE...W wind 30 kt. Seas 11 ft Bering side...19 ft Pacific side.
.TUE NIGHT...SE wind 25 kt becoming SW 35 kt after midnight. Seas
8 ft Bering side...15 ft Pac side. Snow.
.WED AND WED NIGHT...SW wind 35 kt. Seas 18 ft.
.THU...S wind 30 kt. Seas 17 ft.
.FRI THROUGH SAT...S wind 30 kt. Seas 19 ft.

$$

PKZ178-231330-
Kiska to Attu-
346 PM AKST Mon Feb 22 2021

...GALE WARNING TUESDAY NIGHT...

.TONIGHT...NW wind 25 kt. Seas 17 ft.
.TUE...Variable wind 15 kt. Seas 13 ft.
.TUE NIGHT...Bering side...E wind 25 kt increasing to 35 kt after
midnight. Seas 9 ft building to 14 ft after midnight. Pacific 
side...E wind 25 kt becoming SW 40 kt after midnight. Seas 9 ft 
building to 18 ft after midnight. Snow.
.WED...SW wind 40 kt. Seas 19 ft.
.WED NIGHT...SW wind 35 kt. Seas 20 ft.
.THU...S wind 25 kt. Seas 18 ft.
.FRI...W wind 30 kt. Seas 17 ft.
.SAT...E wind 25 kt. Seas 29 ft.

$$

PKZ179-231330-
Pribilof Islands Near Shore Waters-
346 PM AKST Mon Feb 22 2021

...GALE WARNING TONIGHT...

.TONIGHT...SE wind 35 kt becoming SW 20 kt after midnight. Seas 10 
ft.
.TUE...SE wind 25 kt. Seas 10 ft.
.TUE NIGHT...S wind 20 kt becoming W after midnight. Seas 10 ft.
.WED...SW wind 20 kt. Seas 8 ft.
.WED NIGHT...SW wind 30 kt. Seas 14 ft.
.THU THROUGH FRI...S wind 25 kt. Seas 13 ft.
.SAT...W wind 25 kt. Seas 17 ft.

$$

PKZ180-231330-
Kuskokwim Delta and Etolin Strait-
346 PM AKST Mon Feb 22 2021

...GALE WARNING TONIGHT...
...HEAVY FREEZING SPRAY WARNING THROUGH TUESDAY...

.TONIGHT...SE wind 35 kt. Seas in ice free waters 6 ft. Heavy
freezing spray. Snow.
.TUE...S wind 25 kt, except SE 15 kt N of Cape Newenham. Seas in ice
free waters 6 ft. Heavy freezing spray and snow in the morning. Rain
in the afternoon.
.TUE NIGHT...Variable wind 15 kt. Seas in ice free waters 6 ft. 
Rain.
.WED...SW wind 20 kt. Seas in ice free waters 5 ft.
.WED NIGHT...SW wind 30 kt. Seas in ice free waters 9 ft.
.THU...S wind 30 kt. Seas in ice free waters 10 ft.
.FRI...SE wind 20 kt. Seas in ice free waters 7 ft.
.SAT...W wind 25 kt. Seas in ice free waters 8 ft.

$$

PKZ181-231330-
North and West of Nunivak Island-
346 PM AKST Mon Feb 22 2021

...BRISK WIND ADVISORY TONIGHT AND TUESDAY NIGHT...

.TONIGHT...E wind 30 kt. Snow.
.TUE...SE wind 20 kt.
.TUE NIGHT...E wind 25 kt.
.WED...E wind 20 kt.
.WED NIGHT...N wind 15 kt.
.THU THROUGH FRI...E wind 20 kt.
.SAT...NW wind 25 kt.

$$

PKZ185-231330-
Saint Matthew Island Waters-
346 PM AKST Mon Feb 22 2021

...GALE WARNING TONIGHT...
...HEAVY FREEZING SPRAY WARNING THROUGH TUESDAY...

.TONIGHT...E wind 35 kt. Seas in ice free waters 13 ft. Heavy
freezing spray. Snow.
.TUE...E wind 30 kt. Seas in ice free waters 11 ft. Heavy freezing
spray.
.TUE NIGHT...E wind 30 kt. Seas in ice free waters 10 ft. Freezing
spray.
.WED AND WED NIGHT...NE wind 30 kt. Seas in ice free waters 7 ft.
.THU THROUGH FRI...NE wind 35 kt. Seas in ice free waters 14 ft.
.SAT...N wind 30 kt. Seas in ice free waters 13 ft.

$$

Southcentral and Southwest Alaska Forecast Discussion
National Weather Service Anchorage AK
421 PM AKST Sun Feb 21 2021

.ANALYSIS AND UPPER LEVELS...

Light snow is falling from the Soldotna area north through the
Anchorage Bowl and into the Mat-Su Valleys. This snow is falling
out of some low-level cloud cover that is slowly working its way
north. This minor event has developed from instability associated
with a weak shortwave trough moving through the area. Likewise,
on the Alaska Peninsula on-shore flow and weak instability is the
cause of light snow for areas around Bristol Bay. Otherwise, quiet
weather and cold temperatures due to high pressure continue for
mainland AK. The next round of low pressure is also entering the
Western Aleutians.

&&

.MODEL DISCUSSION...

Model performance on the synoptic scale through the short term is
good. However, models completely missed the light snowfall event
ongoing through Southcentral. This resulted in manual edits
through the morning. The closest was the GFS, which only had a
chance of precipitation today. Models also missed precipitation
near King Salmon in Southwest AK. Both appear to be from the
mishandling of a couple shortwave troughs over our forecast area.
From this, we can say model performance on the mesoscale has been
poor for much of our forecast area today.

&&

.AVIATION...

PANC... Light snow and MVFR conditions are expected to continue
through the afternoon. Some light snow showers and patchy fog may
develop at or near the airfield overnight, though there is some
uncertainty if these will develop at the airfield itself.
Therefore, included vicinity showers in the TAF with mist. We are
also expecting MVFR ceilings to redevelop overnight.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 and 2)...

Broad troughing in the upper levels persists through tomorrow,
followed quickly by a short-lived upper level ridge Tuesday and
Tuesday night. Ridging will help clear out the skies across much
of Southcentral by tomorrow afternoon, resulting in cooler
temperatures and drier conditions tomorrow through tomorrow night.
Light snow showers linger across the eastern portion of the
Copper River Basin as well as Cordova and areas east through
tomorrow morning. Cloudy skies and active weather returns Tuesday
afternoon when a shortwave trough pushes towards the North Gulf
Coast. Precipitation is expected across the North Gulf Coast as
well as the Susitna Valley Tuesday afternoon and evening, becoming
more widespread across the Southcentral region, including Kodiak
Island, by Tuesday night. There is still quite a bit of model
inconsistency, especially on Wednesday, with this shortwave with
regards to when it becomes a closed low and its strength. Thus,
specific details still need to be fine tuned.

A tight pressure gradient sets up along the Alaska Range Monday
afternoon, aiding in the strong, gusty flow of cold air across
southern Cook Inlet and through the Barren Islands, as well as
across Kodiak Island, through Monday night. A brief period of
storm force winds are likely west of the Barren Islands, with seas
between 20-30 ft Monday afternoon. Heavy freezing spray will also
be a concern tonight and tomorrow for southern Cook Inlet and
Shelikof Strait. This cold air flow over the warmer waters (think
lake-effect snow) is favorable to create a snow band across
Kachemak Bay and Homer Bluffs. While short-lived, this band would
bring a period of heavy snow and blowing snow, but expected
accumulations remain low. Though not as strong, another tight
pressure gradient exists over the Kenai Mountains, causing winds
to become gusty for both Seward and Resurrection Bay.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 through 3: Sunday
afternoon to Wednesday afternoon)...

An elongated shortwave trough stretched out across the Kuskokwim
Valley southward through west-central Bristol Bay will continue
moving eastward through this evening. Light snow continues to fall
out ahead of it especially for areas east and northeast of King
Salmon. Generally less than a half inch of total accumulation is
expected from this activity by the time it ends this evening.

Next, a more potent closed off upper level low will barrel its way
through Southwest overnight and into the day on Monday. This will
bring a reinforcing shot of Arctic air for Southwest with areas
across the Kuskokwim Delta falling possibly into the 20s below
zero. This will all depend on how much cloud cover actually moves
through as this upper level low passes through. Temperatures
for the Kuskokwim Valley will be in the teens below zero but could
be colder all depending on the amount of cloud cover in place. If
it stays clear, 20s below zero will be possible here as well.
Bristol Bay ranges from single digits below zero inland to single
digits to near zero along the coast.

Lastly, a frontal system currently moving through Shemya and the
western Aleutian Island Chain this afternoon will continue
across the Bering reaching Nunivak Island and the Southwest coast
by Monday evening. Expect the remainder of the forecast period
from Monday through Wednesday afternoon to remain unsettled.
Initially, when the front approaches, there may be a period of
blowing snow along the Kuskokwim Coast and for Nunivak Island. At
this time, it appears to be a brief window Monday evening/early Tuesday
as the front will be weakening on its approach. Snowfall amounts
from Monday night through Tuesday evening range anywhere from 3 to
5 inches across Southwest with a similar amount Tuesday evening
through Wednesday afternoon. Since the snow is not expected to all
come at once, an advisory is not warranted at this time.
Temperatures are also expected to be on the warming trend
beginning on Tuesday leading to the potential for precipitation
type issues mainly from King Salmon south down the Alaska
Peninsula. Right now, continuing to stay with a rain/snow mix for
King Salmon and areas nearby as there is still uncertainty as to
how fast this warm air moves in. Stay tuned for the latest
updates.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 through 3:
Sunday afternoon to Wednesday afternoon)...

Low stratus with embedded snow showers are occurring for the
Pribilofs and areas north and south near the ice edge. Cold air
flowing over the still relatively warm water of the Bering Sea is
creating an unstable atmospheric profile that is generating
clouds and snow showers as a result. Any of these snow showers
will continue to briefly reduce visibility as they pass through
the Pribilof Islands tonight and into early Monday.

The pattern change storm for much of Alaska is on its way with
the front currently moving through the Western Aleutians and the
western Bering Sea. This front will continue moving through the
Bering and into the Southwest Coast Monday evening. Expect
unsettled weather along the entire Aleutian Island Chain for the
forecast period. After the front moves through, the center of the
low will meander in the west-central Bering Sea through Tuesday
night before dissipating. The Pribilofs will remain the tough
precipitation type forecast as enough cold air may hang on to
keep much of any precipitation that moves through as snow.
However, rain may mix in at times. For Dutch Harbor, Cold Bay and
Sand Point, enough warmer air will move in to allow for mostly
rain.

Lastly, another frontal system will move into the Western
Aleutians and the western Bering Sea Monday night continuing the
active pattern and more unsettled weather through mid-week. Also,
heavy freezing spray will continue near the ice edge through mid-
week.

&&

.MARINE (Days 3 through 5:Wednesday through Friday)...

Bering: The eastern Bering low moves inland for Thu. A new low
and front move across the western Bering through Fri. Models are
mixed, but confidence is good. Widespread small craft winds and
waves cover the Bering with the low on Wed, but an area of gale
force winds south of the Aleutians moves into the southern Bering
for Thu, then diminish Fri. Some areas of gale force winds over
the northern Bering linger for Fri. Waves build to 30 feet on the
Pacific side, 20 feet Bering side Thu and Fri.

Gulf of Alaska: A low tracks along the front across the Gulf,
then inland Thu. Widespread gale force winds are expected around
the low through Thu, then diminish to small craft winds on Fri.
Waves build to 20 feet Thu, then subside Fri.

&&

.LONG TERM FORECAST (Days 3 through 7)...

The trend in the long term continues to be an active, zonal
pattern midweek transitioning to a more meridional pattern going
into the weekend. The pattern slows down (as one would expect)
when this transition occurs. However, the pattern looks like it
continues to send troughs and ridges through our area, just at a
higher amplitude and slower pace. So, active weather will continue
through the week. Outside of general agreement on the synoptic
pattern, models have a difficult time. This especially goes for
low pressure centers. So, the long term still looks quite messy.
This means moderate to high confidence in the synoptic pattern,
but low confidence for what comes of it with the weather.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...Storm Warning: 130.
Gale Warning: 120 131-138 165 170 172-174 176 178-185 351 352 411-414.
Heavy Freezing Spray Warning: 130 138 139 141 150 160 179 180 185
                              412 414.

&&

SYNOPSIS AND MODEL DISCUSSION...BJB
SOUTHCENTRAL ALASKA...KM
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...MV
MARINE/LONG TERM...MK/BJB